She has long insisted she was ‘happily unmarried’ – but Kirstie Allsopp has had a change of heart.

These stunning exclusive pictures reveal the Location Location Location star beaming with happiness as she finally tied the knot with her property tycoon beau Ben Andersen last week, in a ceremony she had kept secret until the very last minute – even from most of her guests – in a bid to keep it private.

The elegant, low-key event was held at the Grosvenor Chapel in Mayfair, which was where Love Actually’s wedding scene between Keira Knightley and Chiwetel Ejiofor was sH๏τ.

But it also has deep connections to Kirstie’s family and was where a memorial service for her beloved father, former Christie’s chairman Charles Allsopp, 6th Baron Hindlip, was held last June.

The couple returned to the 18th Century building to take their vows surrounded by around 70 close friends and family, most of whom had only just found out that they were to be attending a wedding. 

Kirstie and Ben – who have been together for 21 years and have two sons, Bay, 18, and Oscar, 16 – had said they were celebrating Ben’s 64th birthday before springing the surprise.

Kirstie, 53, arrived for the service in a stunning gold sequin and tulle customised Oscar de la Renta dress she had bought two weeks earlier.

The joyful 40-minute ceremony included the Beatles’ hit All You Need Is Love, which also featured in Richard Curtis’s Love Actually, and the hymn I Vow To Thee, My Country.

Kirstie Allsopp finally tied the knot with her property tycoon beau Ben Andersen last week 

The couple returned to the 18th Century building to take their vows surrounded by around 70 close friends and family

Kirstie, 53, arrived for the service in a stunning gold sequin and tulle customised Oscar de la Renta dress she had bought two weeks earlier

Kirstie told The Mail on Sunday the arrangements were so last minute and secretive that many important guests – including Phil Spencer, her Channel 4 co-host for more than two decades – were unable to make it.

‘On Thursday, Ben and I were married at The Grosvenor Chapel, where my parents and grandparents were married, and where we celebrated my father’s life in June,’ she said. 

‘We had with us a small group of close friends and family who only heard about the wedding on Monday.

‘We already had a big party planned to mark Ben’s birthday, so most of our guests thought that’s what they were coming to celebrate, and we did just that, with lots of food, drink, and dancing and all my nephews and nieces running around, having a ball.

‘We did sing All You Need is Love. That was Ben’s idea; I am a huge Richard Curtis fan and have an original script from the movie. I bought my sparkly dress two weeks before in the sales, and the lovely ladies at Oscar de la Renta added sleeves, thinking it was for an award ceremony.

‘The flowers, the catering, the order of service and the lighting were all done by people I have worked with over the years who kept it all secret and put together an amazing event at very short notice, though because of that short notice some beloved friends and family couldn’t be there, including Phil.’

The couple’s sons – alongside Ben’s older sons Hal and Orion from a previous relationship – were ushers. All four were seen at a local wine bar before the wedding, with Bay seen practising a speech outside. 

Those attending the ceremony included Kirstie’s sisters, Sofie Fletcher and Natasha Morley, designer India Hicks and Kirstie’s cousin, former hedge fund boss Jamie Allsopp.

Kirstie was introduced to Ben (pictured together), a self-made multi-millionaire, by his ex-wife Theresa, who had attended private school Bedales at the same time as Kirstie

Kirstie and Ben (pictured) have been together for 21 years and have two sons, Bay, 18, and Oscar, 16

Kirstie decided to release official pictures, taken by celebrated pH๏τographer Catherine Bradley, to this newspaper after becoming aware that a paparazzi pH๏τographer had been waiting outside the chapel.

‘I had hoped that we had pulled off a real coup, a genuinely private wedding in the city we love, in a church connected to my family, which also happens to be the Love Actually church,’ she said. 

‘Unfortunately, despite my cunning plan, there was a paparazzi pH๏τographer outside.

‘So, with the help of The Mail on Sunday, I am releasing a few pictures of my own, and if anyone else wants to use them please make a donation to the Grosvenor Chapel, which will soon celebrate 300 years of being at the centre of Mayfair.’ That can be done via grosvenorchapel.org.uk

Kirstie was introduced to Ben, a self-made multi-millionaire, by his ex-wife Theresa, who had attended private school Bedales at the same time as Kirstie.

Until last week, Ben always said he did not want to marry again following his divorce.

Kirstie once said: ‘Ben won’t ever marry me. He sat me down ten days after we’d met and said, ‘I never want to be married again but I’d like to have children with you and live with you for the rest of my life’.

‘It was almost like a proposal. I felt I had to say OK. Ben is an amazing person who I love very much.’